Constant frequency ZVS converter with integrated magnetics

The author introduces a high-frequency DC-DC converter which provides zero-voltage-switching (ZVS) and allows control of the output by pulse width modulation (PWM) at constant frequency. The topology is very tolerant to leakage inductance in the isolating transformer, and it is possible to combine the transformer and filter choke into a single integrated magnetic assembly yielding several additional benefits. The converter has been operated with ZVS to reduce losses at the switching transition, and this has allowed high-frequency operation even with high frequency and high input voltage. A control scheme has been defined whereby constant frequency operation and PWM produce a linear control to output transfer function with minimal interaction of load.<<ETX>>